Feasibility and safety of the direct current cardioversion at the time of left atrial appendage occlusion for patients with atrial fibrillation

Background

With an increasing number of patients undergoing left atrial appendage occlusion (LAAO), more attention is being paid to relieving clinical symptoms and improving the quality of life of these patients. For patients with atrial fibrillation (AF), direct current cardioversion (DCCV) is an alternate, nonpharmacological choice to restore sinus rhythm and relieve clinical symptoms.

Objectives

The purpose of this study was to assess the feasibility and safety of the DCCV at the time of LAAO for patients with AF.

Methods

Forty patients were enrolled in the DCCV group undergoing the DCCV at the time of LAAO. The control group undergoing LAAO alone was formed by 1:1 matching.

Results

In the DCCV group, cardioversion was immediately successful in 30 (75%) patients, of which 12 (40%) had AF recurrence at the three-month follow-up. The failed-DCCV group was older (73.70 ± 4.74 vs. 62.20 ± 9.01 years old, P = 0.000), had a faster postcardioversion heart rate (88.80 ± 16.58 vs. 70.97 ± 14.73 times, P = 0.03), and had a higher mean HAS-BLED score (4.00 vs. 3.00, P = 0.01) than the successful-DCCV group. No patients experienced periprocedural pericardial effusion, occluder displacement, device embolism, or >5 mm peridevice leakage. One patient experienced a transient ischemic attack (TIA) in the DCCV group during the follow-up.

Conclusions

The DCCV at the time of LAAO is feasible and safe for AF patients with contraindications for catheter ablation or AF recurrence after previous catheter ablation to restore the sinus rhythm and relieve clinical symptoms. The DCCV at the time of LAAO is more likely to succeed for younger patients and patients with lower HAS-BLED scores.

Cardiac Tamponade During Catheter Atrial Fibrillation Ablation: A Life-Threatening Complication

Catheter ablation has become an important treatment strategy for the management of atrial fibrillation (AF) in symptomatic patients. Pulmonary vein isolation (PVI) is increasingly used to restore rhythm in patients with AF and flutter. The serious procedural complication rate has significantly reduced over time and most patients undergo PVI without any adverse events. We present the case of a 70-year-old man with symptomatic AF who underwent elective PVI that was complicated by large pericardial effusion from left atrial appendage (LAA) perforation resulting in cardiac tamponade requiring emergency pericardiocentesis followed by sternotomy to suture the LAA. The perforated LAA was sutured and the LAA was closed surgically through sternotomy by using AtriClip and a large amount of blood was evacuated achieving good cardiac output and hemodynamic stability. A surgical PVI was performed twice restoring normal sinus rhythm. The patient was discharged home, however, he returned to the hospital a few days later with atrial flutter with a rapid ventricular response. He underwent direct current cardioversion (DCCV) and remained in sinus rhythm during the rest of his admission. His bisoprolol was switched to Sotalol to maintain normal sinus rhythm and he was discharged home with outpatient follow-up.

Marked QTc Reduction Immediately Following Direct Current Cardioversion of Atrial Fibrillation: Clinical Implications and Mechanisms

BACKGROUND

The QTc in sinus rhythm (SR) following direct current cardioversion (DCCV) of atrial fibrillation (AF) is commonly used as a baseline QTc for patients who require initiation of antiarrhythmic drugs for rhythm control. Inaccurate baseline QTc may cause drug-induced torsades de pointes.

OBJECTIVES

To assess time-dependent QTc changes following DCCV.

METHODS

We prospectively assessed QTc changes with Bazett's QTc and Fridericia's QTc formulas in 65 patients following conversion of AF to SR. Among these 65 patients, 48 underwent DCCV and 17 spontaneously converted to SR.

RESULTS

There was a large and statistically significant decrease in QTc in SR immediately following DCCV in 40 patients, which occurred with an abrupt reduction in heart rate postcardioversion. This finding excluded 8 patients with ventricular-paced QRS. The mean decrease from QTc in AF was 70.7 ± 37.2 milliseconds in the QTc interval for heart rate using Bazett's formula and 33.8 ± 17.9 milliseconds in the QTc interval for heart rate using Fridericia's formula at 1-minute post-DCCV. In 17 patients with spontaneous conversion from AF to SR, the QTc reduction was comparable to those in patients with DCCV. The QTc increased with time and reached a steady state at 5 minutes following conversion. Initiation of class III drugs based on the "shortened" baseline QTc following DCCV was associated with drug-induced torsades de pointes.

CONCLUSIONS

In patients with AF following conversion, regardless spontaneous or DCCV, the QTc shortened significantly with decreases in heart rate, likely via the mechanism of time-dependent rate adaption of ventricular repolarization. A steady-state QTc at 5-minutes following DCCV should be used as real baseline for guidance of pharmacotherapy in patients with AF.

Impact of anticoagulation strategy after left atrial appendage occlusion in patients requiring direct current cardioversion

INTRODUCTION

Current guidelines recommend adequate anticoagulation for at least 3 weeks pre- and 4 weeks post-direct current cardioversion (DCCV) to reduce thrombo-embolic risk in patients with atrial fibrillation (AF) lasting greater than 48 h. No specific recommendations exist for DCCV in patients that have undergone left atrial appendage occlusion (LAAO), many of whom are ineligible for anticoagulation. This study aims to observe the efficacy and safety of DCCV post-LAAO in everyday clinical practice.

METHODS

This prospective multicenter registry included DCCVs in patients post-LAAO. Imaging strategy or anticoagulation treatment around DCCV were analyzed. Complications during 30-day follow-up were registered. DCCVs performed in accordance with current guidelines for the general AF population were compared to DCCVs performed deviating from these guidelines.

RESULTS

In 93 patients (age 65 ± 17 years, CHA₂ DS₂ -VASC 3.0 ± 1.3) 284 DCCVs were performed between 2010 and 2018, in 271 sinus rhythm was restored. A wide variety of imaging or anticoagulation strategies around DCCV was observed; in 128 episodes strategies deviated from current guidelines. No thrombo-embolic events were observed after any DCCV during 30-day follow-up. In 34 DCCVs trans-esophageal echocardiography (TOE) was performed before DCCV to exclude cardiac thrombi and/or (re-)verify adequate device positioning. In two patients without post-LAAO imaging before DCCV, a device rotation or embolization was observed during scheduled TOE after LAAO.

CONCLUSION

DCCV in AF patients after LAAO is highly effective. No thrombo-embolic events were observed in any patient in this observational cohort, regardless of the periprocedural anticoagulation or imaging strategy. Confirmation of adequate device positioning at least once before DCCV seems recommendable.

A Cardioversion and Renal Dysfunction Cascade: Cardioversion for Atrial Fibrillation, Acute Kidney Injury, and Recurrence of Atrial Fibrillation

A 62-year-old woman with hypertension presented with progressively worsening shortness of breath due to acute decompensated heart failure with atrial fibrillation in rapid ventricular response. During admission, she was managed with diuretics, goal-directed medical therapy for heart failure with successful DCCV (Direct current cardioversion) for first episode atrial fibrillation. However, one day after discharge, the patient presented with a recurrence of dyspnea with atrial fibrillation in rapid ventricular response and a reduction in urine output with elevated serum creatinine. In this case report, we describe the syndrome of acute kidney injury following cardioversion for atrial fibrillation known as AFCARD (Atrial Fibrillation Cardioversion Associated with Renal Dysfunction), highlight its incidence and reflect on renal dysfunction subserving the recurrence of atrial fibrillation after successful DCCV.

Echocardiographic assessment of left atrial morphology and function to predict maintenance of sinus rhythm after electrical cardioversion in patients with non-valvular persistent atrial fibrillation and normal function or mild dysfunction of left ventricle

BACKGROUND

The aim of this study was to assess whether echocardiographic measurements of left atrial (LA) morphology and function could predict sinus rhythm maintenance after electrical cardioversion among patients with atrial fibrillation (AF) and normal function or mild dysfunction of the left ventricle (LV).

METHODS

One hundred seventeen patients with persistent AF who underwent successful electrical cardioversion were prospectively enrolled. Echocardiography was performed one day subsequent to successful cardioversion. Patients were followed up clinically and electrocardiographically at 1, 6, and 12 months. At 12 months, 61 (52%) patients had maintained sinus rhythm (SR).

RESULTS

Compared to patients who maintained SR, those with AF recurrence had larger LAs, worse LA systolic function, and increased LV filling pressure. On multivariate stepwise logistic regression, E/A ratios (odds ratio [OR] 0.550, 95% confidence interval [CI] 0.341-0.886; p = 0.014) and E/e' ratios (OR 0.871, 95% CI 0.771-0.985; p = 0.027) were significant predictors of AF recurrence. On receiver operator characteristic curve analysis of AF recurrence at 12 months, the area under curve for both E/A and E/e' ratios were 0.726. With an E/A cutoff of 2.2, the sensitivity for predicting AF recur-rence at 12 months was 72%, and specificity was 73%. With an E/e' cutoff of 9.17, the sensitivity for predicting AF recurrence at 12 months was 72%, and specificity was 74%.

CONCLUSIONS

Left ventricular filling pressure assessed with E/A and E/e' ratios predict AF recurrence after electrical cardioversions among patients with AF and normal function of LV.

Cost-effectiveness of digoxin, pacing, and direct current cardioversion for conversion of atrial flutter in neonates

IntroductionNewborn atrial flutter can be treated by medications, pacing, or direct current cardioversion. The purpose is to compare the cost-effectiveness of digoxin, pacing, and direct current cardioversion for the treatment of atrial flutter in neonates.Materials and methodsA decision tree model was developed comparing the efficacy and cost of digoxin, pacing, and direct current cardioversion based on a meta-analysis of published studies of success rates of cardioversion of neonatal atrial flutter (age<2 months). Patients who failed initial attempt at cardioversion progressed to the next methodology until successful. Data were analysed to assess the cost-effectiveness of these methods with cost estimates obtained from 2015 Medicare reimbursement rates.

RESULTS

The cost analysis for cardioversion of atrial flutter found the most efficient method to be direct current cardioversion at a cost of $10 304, pacing was next at $11 086, and the least cost-effective was digoxin at $14 374. The majority of additional cost, regardless of method, was from additional neonatal ICU day either owing to digoxin loading or failure to covert. Direct current cardioversion remains the most cost-effective strategy by sensitivity analyses performed on pacing conversion rate and the cost of the neonatal ICU/day. Direct current cardioversion remains cost-effective until the assumed conversion rate is below 64.6%.

CONCLUSION

The most cost-efficient method of cardioverting a neonate with atrial flutter is direct current cardioversion. It has the highest success rates based on the meta-analysis, shorter length of stay in the neonatal ICU owing to its success, and results in cost-savings ranging from $800 to $4000 when compared with alternative approaches.

Relationship between brain natriuretic peptides and recurrence of atrial fibrillation after successful direct current cardioversion: a meta-analysis

BACKGROUND

Atrial fibrillation (AF) recurrence is common after successful direct current cardioversion (DCCV), with a 40% rate of recurrence within the first month. Several studies have investigated the potential association between brain natriuretic peptide (BNP) or N-terminal (NT)-proBNP levels before DCCV and the risk of AF recurrence, but results have been inconsistent. We, therefore, conducted a systematic review and meta-analysis of all available data to determine whether sinus rhythm (SR) maintenance after successful DCCV may be determined by preprocedural BNP and NT-proBNP levels.

METHODS

We systematically searched Scopus, the Cochrane library, EMBASE, and MEDLINE databases to identify publications evaluating BNP or NT-proBNP levels in relation to post-DCCV AF recurrence, indexed from inception to September 2013. Among the initial 1,067 citations, 18 studies fulfilled the specified criteria. The difference in BNP and NT-proBNP concentrations in the AF recurrence and the SR-maintaining group was estimated by the standardized mean difference and the estimates of the pooled outcomes were evaluated using random-effects models.

RESULTS

Baseline BNP levels in the AF recurrence group were significantly higher compared to BNP levels in the SR-maintaining group (standardized mean difference [SMD] -1.51, confidence interval [CI] [-2.53, -0.48], P = 0.004). Similar results were observed for NT-proBNP levels, which were significantly higher in the AF recurrence group compared with the SR-maintaining group (SMD -0.63, CI [-1.13, -0.14], P = 0.01).

CONCLUSIONS

Our analysis suggests that low preprocedural BNP/NT-proBNP levels are associated with SR maintenance. The use of BNP or NT-proBNP for prediction of long-term response to DCCV appears to be useful and should be further evaluated.

The role of biphasic shocks for transthoracic cardioversion of atrial fibrillation

The modern generation of transthoracic defibrillators now employ impedance compensated biphasic waveforms. These new devices are superior to those with monophasic waveforms and practice is currently switching to biphasic defibrillators for the treatment of both ventricular and atrial fibrillation. However, there is no universal guideline for the use of biphasic defibrillators in direct current cardioversion of atrial fibrillation. This article reviews the use of biphasic defibrillation waveforms for transthoracic cardioversion of atrial fibrillation.